A communication device performing wireless communication includes a radio frequency (RF) power amplifier for boosting up the power of transmit signals and many other integrated circuits (ICs). The RF power amplifier (PA) in the communication device amplifies RF signals and allows the amplified RF signals to be transmitted through an antenna. As such, power amplifiers may be used to amplify relatively low-power RF signals.
Since the power amplifier and RF front end (e.g., a switch or diplexer) are an analog circuit, they exhibit different characteristics per communication device. Thus, different characteristics per analog circuit need to be calibrated to be consistent in order to adjust the characteristics for RF signal transmission. For example, RF power required for RF signal transmission is subjected to calibration for RF signal transmission in such a manner that the gain of the transmitter and the gain of the power amplifier are adjusted and the output power corresponding to the input power is then measured.
In order to optimize the power consumed in the power amplifier for RF signal transmission, the overall output power has been calibrated for each power mode of the power amplifier and the channel (frequency). For example, when the power amplifier supports three power modes, average power tracking (APT) adjustment and calibration need to be carried out for the overall output power per channel for each of the three power modes in order to optimize the power consumed per channel in the power amplifier.
As such, even output power and power modes not requiring calibration are subjected to calibration. Thus, the time of calibration is prolonged. Further, a gain table or input power values are required to be stored in the APT table and results of calibration, which requires an excessive memory size to be secured.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.